#include "CRC16.h"

void MEM_SET(unsigned char *p, unsigned char v, unsigned char len)
{
    while (len > 0)
    {
        len--;
        p[len] = v;
    }
}
void MEM_CPY(unsigned char *d, unsigned char *s, unsigned char len)
{
    while (len > 0)
    {
        len--;
        d[len] = s[len];
    }
}

//
/*
void uint16_cpy(uint8_t *d, uint8_t *s)
{
    d[0] = s[1];
    d[1] = s[0];
}*/

void uint32_cpy(unsigned char *d, unsigned char *s)
{
    d[0] = s[3];
    d[1] = s[2];
    d[2] = s[1];
    d[3] = s[0];
}

/*                    crc校验表                      */
static const unsigned char aucCRCHi[] =
    {
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
        0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40};

static const unsigned char aucCRCLo[] =
    {
        0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04,
        0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8,
        0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC,
        0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3, 0x11, 0xD1, 0xD0, 0x10,
        0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4,
        0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38,
        0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C,
        0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26, 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0,
        0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4,
        0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68,
        0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C,
        0xB4, 0x74, 0x75, 0xB5, 0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0,
        0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54,
        0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98,
        0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
        0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80, 0x40};
	
/***********************************************************************************************************
* 函数名称: CRC16MODBUS()
* 输入参数: *pucFrame,待校验数据首地址，usLen为待校验数据长度
* 返回值  : 校验结果
* 功    能: CRC-16 MODBUS 校验函数
************************************************************************************************************/
unsigned short CRC16MODBUS(unsigned char *pucFrame, unsigned short usLen)
{
    unsigned char ucCRCHi = 0xFF;
    unsigned char ucCRCLo = 0xFF;
    int iIndex;
    while (usLen--)
    {
        iIndex = ucCRCLo ^ *(pucFrame++);
        ucCRCLo = (unsigned char)(ucCRCHi ^ aucCRCHi[iIndex]);
        ucCRCHi = aucCRCLo[iIndex];
    }
    return (unsigned short)(ucCRCHi << 8 | ucCRCLo);
}

/***********************************************************************************************************
* 函数名称: PackageSendData()
* 输入参数: data,要发送的数据的首地址； *len,发送数据的总长度
* 返回值  : 无
* 功    能: 根据通信协议，封装要发送的数据
************************************************************************************************************/

void PackageSendData(unsigned char *dat,unsigned char *len)
{
    unsigned char temp[32];
    unsigned char i, j = 0,k = 0;
    unsigned short crc;
	  MEM_SET(&temp[0], 0, sizeof(temp));
    temp[k++] = FrameHeader;                //加入帧头
		temp[k++] = *len + 3;                    //加入长度值  不包括帧头帧尾

    MEM_CPY(&temp[k], dat, *len);          //复制传输数据s		
    crc = CRC16MODBUS(&temp[1], *len + 1); //计算CRC16校验值
    temp[*len + 2] = (crc >> 8) & 0xff;
    temp[*len + 3] = crc & 0xff;
    MEM_CPY(dat, temp, *len + 4);
    //判断是否有需要添加转义字符，校验位最后一位不判断。
    for (i = 3; i < *len + 3; i++)
    {
        if ((temp[i] == FrameHeader) || (temp[i] == FrameEnd)) //如果传输的数据中有和帧头或帧尾一样的数据则插入转义符
        {
            dat[i + j] = 0x5c;
            dat[i + j + 1] = temp[i];
            j++;
        }
        else
        {
            dat[i + j] = temp[i];
        }
    }
    dat[*len + 4 + j] = FrameEnd;
		*len  = *len + 5 + j;

}

unsigned int GetCRC16(unsigned char *ptr,  unsigned char len)
{
    unsigned  short int index;
    unsigned char crch = 0xFF;  //高CRC字节
    unsigned char crcl = 0xFF;  //低CRC字节
    

    while (len--)  //计算指定长度CRC
    {
        index = crch ^ *ptr++;
        crch = crcl ^ aucCRCHi[index];
        crcl = aucCRCLo[index];
    }

    return ((crch<<8) | crcl);
}



unsigned char CRC_Check(unsigned char *ptr,unsigned  char len)
{
    unsigned short int CRCA;
    unsigned char  CRCH;
    unsigned char  CRCL;
    CRCA = GetCRC16(ptr,len-2);
    CRCH = CRCA>>8;
    CRCL = (unsigned char)CRCA;
    if(CRCH==ptr[len-2]&&CRCL==ptr[len-1])
        return 1;
    else return 0;
}

unsigned char CRC_Check2(unsigned char *ptr,unsigned  char len)
{
    unsigned short int CRCA;
    unsigned char  CRCH;
    unsigned char  CRCL;
    CRCA = GetCRC16(ptr,len-2);
    CRCH = CRCA>>8;
    CRCL = (unsigned char)CRCA;
    if(CRCH==ptr[len-1]&&CRCL==ptr[len-2])
        return 1;
    else return 0;
}

